At the age of nineteen, following his father's remarriage, Ryō, until then an only child, suddenly finds himself with three little brothers: Kentō, Hayato and Masato. After the death of his father, and then his stepmother, life becomes more complicated, but despite the hardships, the four brothers form a close bond and manage to overcome the trials of life. Four years later, Ryō has taken over his mother-in-law's cafe and lives a fulfilling relationship with Hayato. Kentō, on the other hand, works with Ryō at the café and is dating Take, Masato's best friend. While Kentō and Take have to deal with the growing fame of the latter, a rising TV star, Hayato and Ryō are struggling to find their feet, sex-wise...